The major purpose of this proposed study is to develop the technique and clinically evaluate methods to assess the effectiveness of using motion simulation to sooth infants who are diagnosed as having colic. Although colic is one of the most common problems seen in pediatric practice (estimates of incidence range from 9 to 23% of the one to three month old population), it is not well understood and there are few effective treatments. Clinical reports and results of laboratory research strongly support the use of rhythmic, rocking motion, or rocking-vibration to sooth infants who often have fussy, colicky episodes. Even with this knowledge about the effectiveness of motion/vibration, there is no commercially available product to provide soothing motion/vibration aimed at easing colicky episodes in infants. The specific aims of this research are, 1) to better understand and document characteristics of colic in infants so that recommendations about the application of motion simulation will be optimally useful upon the effectiveness; 2) to refine the motion simulation prototype and its application; and 3) to develop ways to measure the effectiveness of motion simulation in soothing infants who have colic. Phase I Pilot clinical trials will be conducted on 10 infants diagnosed as having colic. A within subject's design will be used wherein each of the 10 infants serves as his own control and experiences a 5-day trial with the motion simulator alternated with a 5-day trial with a placebo. Measures of the effectivness of the treatment include data provided by a 24-hour, parent-kept diary and data from behavioral observations during episodes of colic conducted by a pediatric nurse. The potential benefits are the development of a product that will significantly reduce colic and mainly will: 1) ease infant pain and discomfort, 2) decrease the use of drugs, 3) minimize child abuse, 4) displace pediatricians' time to be devoted to other illnesses, and 5) improve the quality of family relations. Findings from this preliminary Phase I study will demonstrate the feasibility of mounting a major research and development effort (Phase II) and will provide data to guide the design of that study.